To provide a safe and efficient operation, air entering a gas turbine for power generation applications is filtered. The gas turbine air inlet system may include an inlet filter house and associated ducting. In a typical installation, there may be between 300 and 800 filter elements attached to and projecting from a tube sheet, depending on the frame size of the turbine.
Current air filtration systems in service may be equipped with a functional self-cleaning system that utilizes compressed air to discharge a “puff” or blast of air into the filters to dislodge particles and debris and thus clean the filters. Standard operating methodology for the pulse control system for self-cleaning is driven by timers and solenoid valves sequencing that releases compressed air to “puff” the filters and dislodge particles.
Proper maintenance of gas turbine air filtration systems is critical. Poor quality air can significantly impact the operation, performance and life of a gas turbine. It is important that filters be cleaned or replaced once they are fully loaded with dust particles. Self-cleaning air filtration systems are automated systems which clean themselves when the pressure change across the filters reaches a specified level. This is completed through reverse air pulses. The degree of fouling of filters varies depending upon the location of the filter on the inlet filter house. Current filter systems do not provide adequate indication of fouling of specific filters or groups of filters. Consequently, filters may be cleaned or replaced unnecessarily.